The long term objective of this proposal is to investigate the underlying mechanisms of brain repair. A normal brain receives stimuli and information and responds to its environment. A damaged brain attempts the same process, but has the added task of reorganization through interactions between neurons and the immediate and external environments. Post-traumatic environmental conditions, both physical and social, can enhance or impede the brain repair process. In this proposal, experiments are proposed to explore and identify aspects of social properties that facilitate brain recovery and the role of neurogenesis in the improvement of brain function. Specifically, discrete lesions in the hypothalamus will be used to experimentally render male ring doves unable to perform courtship behaviors when initially introduced to a female. It has previously been shown that housing a male who has lesion damage with a mature female will facilitate the full recovery of courtship behavior. In experiments designed to determine which environmental factors may play a role in the reinstatement of courtship behavior, brain damaged males will be exposed to a variety of social conditions. Additionally, preliminary studies of adult ring doves strongly suggest that brain lesions dramatically increase ventricular mitotic activity. With the use of the Hu protein (a family of neuronal RNA-binding proteins) as an early marker of neuronal phenotypic differentiation, the PI plans to demonstrate that neurogenesis is promoted by brain lesions and to explicate the role of neurogenesis in brain repair. Despite a recent surge in the study of brain repair, the possible role played by neurogenesis in the recovery of function have been virtually ignored. Results of the proposed studies will address this question directly and may lead to a promising new direction for the investigation of mechanisms of brain repair after injury.